Effects of repetitive transcranial magnetic stimulation on lower extremity spasticity and motor function in stroke patients

Purpose: To investigate the effect of low-frequency repetitive transcranial magnetic stimulation (rTMS) on lower extremity (LE) spasticity, motor function and motor neurone excitability in chronic stroke patients. Method: This study was a randomised sham-controlled cross-over trial with 1-week follow-up. A total of 20 post-stroke patients were randomised to receive active (n = 10) or sham (n = 10) rTMS. Fourteen of them (7 in each group) crossed over to the sham or active rTMS after a washout period of 1 month. Interventions consist of five consecutive daily sessions of active or sham rTMS to the unaffected lower extremity motor area (1000 pulses; 1 Hz; 90% of the tibialis anterior motor threshold). Outcome measures were modified modified ashworth scale (MMAS), the H-reflex, lower extremity section of Fugl-Mayer assessment (LE-FMA) and timed UP and GO (TUG) test. All outcomes were measured at three levels in each intervention period: pre- and post-intervention and 1-week follow-up. Results: Friedman's test revealed significant improvement in MMAS score only after active rTMS. This improvement lasted for one week after the active rTMS. Repeated measure analysis of variance (ANOVA) showed significant time*intervention interaction for LE-FMA. There are no differences between groups for the MMAS and LE-FMA. No significant change in H-max/M-max ratio and TUG test was noted. Conclusion: Low-frequency rTMS over the LE motor area can improve clinical measures of muscle spasticity and motor function. More studies are needed to clarify the changes underlying this improvement in spasticity.